The present invention relates to well drilling equipment, and more particularly to a tool adapted for use in a subterranean location, where it becomes exposed to drilling fluids and solid particles present in that location.
At the present time a major part of well drilling tools, such as stabilizers, drilling bits, and the like are constructed from steel, having a grade of 4140 or 4141.
While such steel appears to be appropriate for well drilling operations, it has a definite disadvantage in that it tends to absorb, through its micro-pores, drilling fluids and solid particles which in the industry are generally referred to as "Gumbo". Once this gumbo penetrates into the pores, it becomes extremely difficult to remove it by any conventional means, especially if the stabilizer and the drilling bit are in a subterranean location.
Such accumulation of deposit on the drilling tool often causes a jam above and below the stabilizer and sometimes requires many days of circulation of cleaning compositions through the drilling string, so as to get rid of the deposits at least on the annular walls surrounding the well, so as to retrieve the drilling tool and either replace it or attempt to clean it.
It is apparent that such interruption of a drilling process causes a considerable financial loss which will continue to mount while the well is cleaned to retrieve the drilling equipment.
A number of manufacturers attempted to solve the problem of gumbo penetration into the pores of a ferrous core, one of the solutions being the use of Monel equipment on the core, so as to fill the pores and prevent accumulation of the foreign matter on the drilling equipment. However, the cost of any equipment considerably rises with the use of Monel or stainless steel.
It is therefore the main object of the present invention to provide an improved tool and process for treating a surface of the tool to prevent "Gumbo" accumulation on the drilling tool.